DHCP from does not work on fiber router with DHCP disabled.

I've hooked up a TP-LINK Deco M5 to my Huawei fiber router and disabled DHCP on on it, so the Deco manages everything.

I happen to have a PC right next to the fiber connection so I rather use a network cable instead of a WiFi adapter on it and 

if I hook it up via cable to the Huawei router the DHCP from the Deco is not propagated and I must use manual IP address
settings on the PC to get it to work, this is fine for the PC but I also happen to have a wired extender hooked up to the Huawei
which worked fine when DHCP was enabled but now all clients connected to this range extender will also required manual IP

address settings.

I was hopping that plugging a cable to the Huawei would reach out to the Deco to get the IP address, if it was advertising to be
the DHCP authority in the network but that does not seem to be the case, I've attached a diagram here, so far the only solution
I found would be to run another cable from the deco secondary ethernet port to a switch and hook up the computer and extender
to the switch instead but would be nice to not have to do that as well and keep it simple.

I could have the Deco in Access Point mode and keep DHCP in the Huawei but I would loose all the features from the Deco (NAT,

Parental Control, QoS, etc, etc)

Edited by paul-2011, 05 September 2023 - 12:30 PM.

Your current setup appears to be using two routers so there are two local network gateways -- one the primary and the other the secondary, with DHCP disable on one. So there are two local networks in conflict with each other. Your intended setup should be reconfigures so there's just one gateway. That sole gateway will be what manages and maintains everything within that sole local network.

It's not just a matter of disabling DHCP in one, you need to reconfigure your routers to enable 'bridge mode'.

https://www.howtogeek.com/867942/what-is-router-bridge-mode/

The result should be your primary router is your gateway and your secondary router, with all its routing functionality altered is working as just a network switch/WiFi access point.

Also, regarding the Ethernet cable you have in between your Huawei fiber router and your discrete TP-Link router, the cable end in the primary is of course a  LAN port but in your secondary also use a LAN port (don't use the WAN port).